HIV AIDS diagnostic study of choice: Difference between revisions
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== Overview == | == Overview == | ||
In 1980s, AIDS was first recognized and used to be diagnosed with simple serologic testings that detected HIV antibodies using culture derived viral antigen preparations. Later on with passing time, various serological assays were developed that used different testing formats, antigen designs and signal detection amplification chemistries assessing their testing accuracy to ensure that the patient is correctly diagnosed and followed with health care services. This spectrum of testing include Rapid testing, Screening assays and Supplementary confirmation tests. These assays has proven to be beneficial in reducing testing times and improving health care delivery in resource limited settings. | |||
== Diagnostic Study of Choice == | == Diagnostic Study of Choice == | ||
Revision as of 10:24, 16 December 2020
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Kanwal Khamuani
Overview
In 1980s, AIDS was first recognized and used to be diagnosed with simple serologic testings that detected HIV antibodies using culture derived viral antigen preparations. Later on with passing time, various serological assays were developed that used different testing formats, antigen designs and signal detection amplification chemistries assessing their testing accuracy to ensure that the patient is correctly diagnosed and followed with health care services. This spectrum of testing include Rapid testing, Screening assays and Supplementary confirmation tests. These assays has proven to be beneficial in reducing testing times and improving health care delivery in resource limited settings.
Diagnostic Study of Choice
Study of choice
Fourth generation test(ELISA/ELI/MEIA/ELFA/ECLIA) have high sensitivity; therefore they are used as confirmatory test. These test can detect both p24 antigen as well as HIV antibodies.[1]
Screening Immunoassays
There have been five generations of enzyme immunoassays(EIAs) that use different [[antigen] compositions and detection chemistries to give precise and high volume samples for laboratories.[2]
- First Generation Assay: It used antigen lysate preparations to detect antibodies; however due to high false positivity it was replaced by highly specific immunoassays and western blot techniques.
- Second Generation Assay: Proteins derived from Immunodominant regions(IDR) of HIV-1 proteins and gp36 of HIV-2 were used to increase sensitivity and decrease false positivity.
- Third Generation Assay: Detection of Ig G antibodies by using antigens such as gp160 derived from HIV-1 group M, recombinant p24, recombinant peptide from HIV-2 gp36 IDR and synthetic peptide from HIV-1 group O. It also detected HIV-1 IgM to further reduce window period.
- Fourth Generation: It detected both antigen and antibodies at the same time using fully automated chemiluminescent microparticle.
- Fifth Generation: It used multiplex format to detect distinguished p24 antigen of HIV-1 and HIV-2.
Confirmatory Immunoassays
The specimens that were reactive with EIAs need to be retested with more specific confirmatory test which is Western Blot using a gradient purified HIV lysate, electrophorese and suffused onto nitrocellulose strips. For WB to be considered positive, it has to contain antibodies reactive to p24 antigen and envelope glycoproteins.[2]
Rapid Testing Assays
The rapid tests is completed in about 20-30 mins making it ideal in primary care and mobile clinics. Non-laboratory staff can perform these test as it require finger prick blood sample or oral fluid. Although these are less sensitive than EIAs; however, their specificity is higher. [2]
The comparison of various diagnostic studies for [disease name]
| Test | Sensitivity | Specificity |
|---|---|---|
| Test 1 | ...% | ...% |
| Test 2 | ...% | ...% |
[Name of test with higher sensitivity and specificity] is the preferred investigation based on the sensitivity and specificity
Diagnostic results
The following finding(s) on performing [investigation name] is(are) confirmatory for [disease name]:
- [Finding 1]
- [Finding 2]
Sequence of Diagnostic Studies
The fourth generation assays(EIAs, RDTs, CLIAs, ECLs) are performed when HIV is suspected.[3]
- A reactive test is followed by confirmatory second assay from any other fourth generation test.
- A nonreactive test is reported as a negative HIV patient.
If a second line assay is positive:
- It is followed by a retesting prior to starting ART.
If a second line assay is negative:
- Both first line and second line assay are repeated.
Upon repetition if both test give same results as above:
- perform third line assay
Upon repetition if both are negative:
- It is reported as HIV negative patient or the test is repeated agin if high risk features are present.
If results of third line are positive:
- patient is asked to be retested after 14 days
If results of third line assay are negative:
Name of Diagnostic Criteria
It is recommended that you include the criteria in a table. Make sure you always cite the source of the content and whether the table has been adapted from another source.
[Disease name] is primarily diagnosed based on clinical presentation. There are no established criteria for the diagnosis of [disease name].
OR
There is no single diagnostic study of choice for [disease name], though [disease name] may be diagnosed based on [name of criteria] established by [...].
OR
The diagnosis of [disease name] is made when at least [number] of the following [number] diagnostic criteria are met: [criterion 1], [criterion 2], [criterion 3], and [criterion 4].
OR
The diagnosis of [disease name] is based on the [criteria name] criteria, which includes [criterion 1], [criterion 2], and [criterion 3].
OR
[Disease name] may be diagnosed at any time if one or more of the following criteria are met:
- Criteria 1
- Criteria 2
- Criteria 3
OR
IF there are clear, established diagnostic criteria
The diagnosis of [disease name] is made when at least [number] of the following [number] diagnostic criteria are met: [criterion 1], [criterion 2], [criterion 3], and [criterion 4].
OR
The diagnosis of [disease name] is based on the [criteria name] criteria, which include [criterion 1], [criterion 2], and [criterion 3].
OR
The diagnosis of [disease name] is based on the [definition name] definition, which includes [criterion 1], [criterion 2], and [criterion 3].
OR
IF there are no established diagnostic criteria
There are no established criteria for the diagnosis of [disease name].
References
- ↑ Zulfiqar HF, Javed A, Afroze B, Ali Q, Akbar K; et al. (2017). "HIV Diagnosis and Treatment through Advanced Technologies". Front Public Health. 5: 32. doi:10.3389/fpubh.2017.00032. PMC 5339269. PMID 28326304.
- ↑ 2.0 2.1 2.2 Parekh BS, Ou CY, Fonjungo PN, Kalou MB, Rottinghaus E, Puren A; et al. (2019). "Diagnosis of Human Immunodeficiency Virus Infection". Clin Microbiol Rev. 32 (1). doi:10.1128/CMR.00064-18. PMC 6302353. PMID 30487166.
- ↑ Fearon M (2005). "The laboratory diagnosis of HIV infections". Can J Infect Dis Med Microbiol. 16 (1): 26–30. doi:10.1155/2005/515063. PMC 2095005. PMID 18159524.